East Anglia with 33Mm on Average Across the Area, Although with Significant Local Variation
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Monthly water situation report East of England Summary – August 2021 August had below normal rainfall in East Anglia with 33mm on average across the area, although with significant local variation. Soil Moisture Deficit (SMD) continued to increase but remains normal for the time of year. As expected river flows reduced throughout August at almost all indicator sites, although rivers in the North Norfolk catchments retained flows above normal or higher. Groundwater levels also continued to reduce, but all indicator sites in East Anglia remain normal or higher for the time of year and reflecting this, environmental support remained similar to July. All reservoir levels in the area remain above the normal operating curve. Rainfall East Anglia had an average of 33mm of rainfall in August which is classified as below normal for the time of year with 64% of the Long Term Average (LTA). The majority of the rainfall fell at two points within the month around the 5th-9th and 21st-22nd. The rainfall distribution was quite varied with the North Norfolk catchment receiving 46mm (77% LTA; normal) and North and South Essex catchments receiving 40 and 38mm respectively (83% and 82% LTA; normal), whilst the Little Ouse and Lark catchment had only 28mm and was classified as notably low (52% LTA). Totals over the previous 12 months across the area remain above normal with 122% of LTA recorded. Soil Moisture Deficit/Recharge SMD continued to increase throughout the month of August, albeit with a slight decrease in the second week in response to the rainfall. By the end of the month the SMD value reached 106mm, which is still classified as normal for the time of year. A similar spatial pattern to the previous month remains with slightly lower values to the south west and higher values to the north and around the coast. River Flows River flows throughout East Anglia continued to decrease during August at all indicator sites, as expected for the time of year, with the exception of the river Bure in North Norfolk. Across the area 86% of flows at indicator sites remain normal or higher, with 29% above normal and the river Burn in North Norfolk sustaining notably high flows for the time of year. The rivers Cam, Waveney and Tove all recorded below normal flows in August. Groundwater Levels Groundwater levels at all reported indicator sites continued to reduce in August, again as expected for the time of year. However, all sites in East Anglia remain normal or higher for the time of year with 50% of recorded sites having above normal levels. 17% of sites still retain notably high levels for the time of year – Bircham Newton in the North West Norfolk Chalk, Biggleswade in the Ivel Sandstone and Fringford in the Great Oolite. Reservoir Storage/Water Resource Zone Stocks Reservoir levels have remained steady at two of the five reservoirs in the area (Grafham and Hanningfield) and have slightly reduced at three of the five reservoirs (Ardleigh, Abberton and Alton). All reservoirs end the month above their normal operating curve and, with the exception of Abberton which is classified as normal, all have levels classified as above normal or higher for the time of year. Environmental Impact Groundwater support scheme operations have largely remained the same in August, with a slight increase in pumping hours for pumps already in operation. The Lodes-Granta groundwater support scheme had 4 of the 6 pumps operating while the Rhee groundwater support scheme had 2 of the 8 pumps operating. The Hiz and Thet-Little Ouse schemes both remained with no pumping. All data are provisional and may be subject to revision. The views expressed in this document are not necessarily those of the Environment Agency. Its officers, servants or agents accept no liability for any loss or damage arising from the interpretation or use of the information, or reliance upon views contained herein. © Environment Agency 2021 Forward Look Probabilistic ensemble projections for river flows at key sites September 2021: There is an increased probability of flows above normal or higher in the Ivel, and of notably high flows in the Bedford Ouse and Ouse in September. There is a significantly increased probability of below normal flows in the Ely Ouse. All sites (except the Gipping) have a reduced probability of notably or exceptionally low flows in September. December 2021: There is a reduced probability of exceptionally low flows in December, and an increased probability of above normal flows in the Upper Ouse catchment. Probabilistic ensemble projections for groundwater levels in key aquifers September 2021: There is a significantly increased probability that groundwater levels will be normal or above normal at all key sites in September. March 2022: There is a reduced probability of exceptionally low groundwater levels at Bircham Newton and Washpit Farm, Rougham in the North West Norfolk Chalk in March 2022. There is a slightly increased probability of groundwater levels below normal or lower at Newmarket (Snail Chalk) and Kenninghall (Little Ouse Chalk). Author: ANG-Hydrology Contact details: 03708506506 All data are provisional and may be subject to revision. The views expressed in this document are not necessarily those of the Environment Agency. Its officers, servants or agents accept no liability for any loss or damage arising from the interpretation or use of the information, or reliance upon views contained herein. © Environment Agency 2021 Rainfall August 2021 Page | 3 © Environment Agency 2021 Above average rainfall Below average rainfall 1-Month Period for East Anglia 1-Month Period for Upper Bedford Ouse 250% 300% 250% 200% 200% 150% 150% 100% 100% 50% 50% 0% 0% Mar-21 Mar-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 1-Month Period for Lower Bedford Ouse 1-Month Period for Central Area Fenland 250% 250% 200% 200% 150% 150% 100% 100% 50% 50% 0% 0% Mar-21 Mar-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 1-Month Period for Cam 1-Month Period for NW Norfolk and Wissey 250% 250% 200% 200% 150% 150% 100% 100% 50% 50% 0% 0% Mar-21 Mar-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 1-Month Period for Little Ouse and Lark 1-Month Period for North Norfolk 250% 250% 200% 200% 150% 150% 100% 100% 50% 50% 0% 0% Mar-21 Mar-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 Page | 4 © Environment Agency 2021 Above average rainfall Below average rainfall 1-Month Period for Broadland Rivers 1-Month Period for East Suffolk 250% 250% 200% 200% 150% 150% 100% 100% 50% 50% 0% 0% Mar-21 Mar-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 1-Month Period for North Essex 1-Month Period for South Essex 300% 350% 300% 250% 250% 200% 200% 150% 150% 100% 100% 50% 50% 0% 0% Mar-21 Mar-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 Sep-20 Oct-20 Nov-20 Dec-20 Jan-21 Feb-21 Apr-21 May-21 Jun-21 Jul-21 Aug-21 Page | 5 © Environment Agency 2021 Soil Moisture Deficit Data based on MORECS dataset (Met Office © Crown Copyright) ─── 2020-21 ─ ─ ─ 2019-20 Exceptionally high Notably high Above normal Normal Below normal Notably low Exceptionally low ─── Latest data East Anglia Ranking derived from data for the period Jan-1961 to Dec-2017 0 20 40 60 80 SMD SMD (mm) 100 120 140 Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Page | 6 © Environment Agency 2021 River Flow August 2021 Exceptionally high Notably high Above normal Normal - - - - Max Below normal Notably low Exceptionally low ─── Latest data - - - - Min Cappenham, TOVE Willen, OUZEL Ranking derived from data for the period Feb-1962 to Dec-2017 Ranking derived from data for the period Jan-1962 to Dec-2017 6.0 9.0 8.0 5.0 7.0 4.0 6.0 5.0 3.0 4.0 2.0 3.0 Flow (cumecs)Flow (cumecs)Flow 2.0 1.0 1.0 0.0 0.0 Nov-20 Jan-21 Mar-21 May-21 Jul-21 Sep-21 Nov-20 Jan-21 Mar-21 May-21 Jul-21 Sep-21 Page | 7 © Environment Agency 2021 Exceptionally high Notably high Above normal Normal - - - - Max Below normal Notably low Exceptionally low ─── Latest data - - - - Min Burnt Mill, RHEE Roxton, GREAT OUSE Ranking derived from data for the period Oct-1962 to Dec-2017 Ranking derived from data for the period Oct-1972 to Dec-2017 7 50 6 5 40 4 30 3 20 Flow (cumecs)Flow Flow (cumecs)Flow 2 10 1 0 0 Nov-20 Jan-21 Mar-21 May-21 Jul-21 Sep-21 Nov-20 Jan-21 Mar-21 May-21 Jul-21 Sep-21 Blunham, IVEL Offord (Gross Flows), GREAT OUSE Ranking derived from data for the period Aug-1959 to Dec-2017 Ranking derived from data for the period Jan-1972 to Dec-2017 12 70 10 60 8 50 6 40 30 4 Flow (cumecs)Flow Flow (cumecs)Flow 20 2 10 0 0 Nov-20 Jan-21 Mar-21 May-21 Jul-21 Sep-21 Nov-20 Jan-21 Mar-21 May-21 Jul-21 Sep-21 Dernford, CAM Temple, LARK Ranking derived from data for the period Feb-1949 to Dec-2017 Ranking derived from data for the period Nov-1960 to Dec-2017 5.0 5.0 4.5 4.5 4.0 4.0 3.5 3.5 3.0 3.0 2.5 2.5 2.0 2.0 Flow (cumecs)Flow Flow (cumecs)Flow 1.5 1.5 1.0 1.0 0.5 0.5 0.0 0.0 Nov-20 Jan-21 Mar-21 May-21 Jul-21 Sep-21 Nov-20 Jan-21 Mar-21 May-21 Jul-21 Sep-21 Abbey Heath, LITTLE OUSE Northwold Total, WISSEY Ranking